Evaluation of detection ability of regional radar network in complex terrain based on digital elevation model: a sample study of Fujian province in China

摘要

Many countries employ weather radar networks to provide data for weather forecasting offices and research institutes, but most of the stations are located in mountainous regions, where terrain obstacles cause beam blockage. The authors propose a method for evaluating the detection ability of weather radars by combining radar range charts with iso-beam heights and maps of beam exposure intensity. First, methods of drawing radar range charts with iso-beam heights and maps of beam exposure intensity are introduced. Subsequently, the detection ability of the regional weather radar network in Fujian Province, China is evaluated by selecting data from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Global Digital Elevation Model (GDEM). During the evaluation, the radar coverage ratio, height-area index, and beam power loss ratio are chosen as indicators. These three parameters describe the radar coverage of Fujian Province from many aspects in detail. The main conclusions of this study are that radar range charts with iso-beam heights, and maps of beam exposure intensity can accurately indicate the detection ability of weather radars and that echo reflectivity needs to be corrected according to the beam exposure intensity rather than the degree of beam blockage caused by terrain obstacles.